The present invention relates to a novel indole-containing peptide having an antihypertensive activity and/or heart failure curing activity and a process for preparing the same.
It has been known that atrial natriuretic peptide (ANP) secreted from atrial myocytes has strong diuretic, natriuretic and vasodilating activities and inhibitory activity on the renin-angiotensin-aldosterone system, and that ANP is effective for curing hypertension and heart failure. However, ANP itself is a polypeptide and poorly absorbed in the digestive tracts, so that its administration is limited to the parenteral route.
On the other hand, it has been known that ANP is inactivated by neutral metalloendopeptidase, and that the inhibitor of the enzyme can be used as a medicine for curing hypertension and/or heart failure because it increases the concentration of ANP in the blood.